FIG. 17 is a circuit diagram showing the operation a conventional heat pump type of room cooling and heating device (hereafter referred to as an air conditioner) at the time of room heating, as disclosed in, e.g., Japanese Unexamined Utility Model Publication No. 42335/1982. In FIG. 17, reference numeral 1 designates a closed type of compressor for the air conditioner. Reference numeral 2 designates an intake tube for the compressor 1. Reference numeral 3 designates a discharge tube for the compressor 1. Reference numeral 4 designates a four port valve which switches the flowing direction of the gaseous refrigerant discharged from the discharge tube 3. At the time of room heating, the gaseous refrigerant having high temperature is led to an indoor heat exchanger 5 through the four port valve 4, is led to an outdoor heat exchanger 7 through an expansion valve 6, and is returned to the intake tube 2 for the compressor 1 through the four port valve 4. FIG. 17 is the circuit diagram showing the switching position which the four port valve 4 takes at the time of room-heating, while FIG. 18 a basic circuit diagram on room-cooling wherein the four port valve 4 is omitted in order to make the operation of the circuit easily understandable.
By the way, a conventional domestic refrigerator has on the back a structure as shown in FIG. 19. A conventional three door type of refrigerator has a structure as shown in FIG. 21 in a vertical section.
In FIGS. 19 and 21, reference numeral 8 designates a refrigerator cabinet. Reference numeral 9 designates a machine compartment. Reference numeral 10 designates a compressor. Reference numeral 11 designates a condensor. Reference numeral 13 designates an evaporator. Reference numeral 87 designates a subcondenser for drain evaporation. Reference numeral 90 designates a drain pan. Reference numeral 91 designates a freezing compartment. Reference numeral 92 designates a refrigerating compartment. Reference numeral 93 designates a vegetable compartment. Reference numeral 94 designates a low pressure refrigerant pipe. Reference numerals 95 designate doors for the refrigerator.
The refrigerator cabinet 8 includes the machine compartment 9 to house the compressor 10 in it, and it has its rear surface provided with a meander form of condenser 11. The refrigerating circuit for the domestic refrigerator is shown in FIG. 20 wherein reference numeral 12 designates a capillary tube. It is understandable that the refrigerating circuit for the domestic refrigerator has the same constituent elements as the cooling circuit of the air conditioner at room cooling as shown in FIG. 18.
The operations of the air conditioner and the refrigerator will be explained. Since the operation of the refrigerator is the same as that of the air conditioner at room cooling, the explanation will be made in reference to FIG. 18. Now, the operation of the air conditioner at room cooling will be explained.
Domestic air conditioners usually use Freon 22 (hereafter referred to as R-22) as the refrigerant. In FIG. 18, the refrigerant which is discharged from the discharging tube 3 of the compressor 1 in the form of gas having high temperature and high pressure is led to the outdoor heat exchanger 7 where the gas is liquefied while being cooled. The liquefied R-22 is given adiabatic expansion by the expansion valve 6, and it is led to the indoor heat exchanger 5 where the liquefied R-22 absorbs heat energy from the air in the room and becomes a gaseous form. After that, the refrigerant R-22 is returned to the intake tube 2 of the compressor 1.
At the time of room heating, the four port valve 4 switches the flow direction of the refrigerant as shown in FIG. 17 so that the indoor heat exchanger 5 comes into a higher temperature state and the outdoor heat exchanger 7 comes into a lower temperature state to carry out room heating.
On the other hand, domestic refrigerators usually use Freon 12 (hereafter referred to as R-12) as the refrigerant. Since, unlike air conditioners refrigerators do not require a heating function, the four port valve 4 as shown in FIG. 17 is not needed. Because in refrigerators the heat exchangers do not come into different temperature states depending on cooling or heating operation (unlike air conditioners), one of the exchangers is constantly called a condenser and the other is called an evaporator. As stated above, the operation of refrigerators is the same as that of the air conditioners on cooling as explained in reference to FIG. 17.
Although conventional domestic air conditioners have room cooling and room heating functions, the air conditioners are driven in limited periods in one year. Even when they are driven, they are not always driven all day long, and, for example, they are not usually driven at night. With the conventional air conditioners, there is a problem with small operating efficiency.
On the other hand, conventional domestic refrigerators use the refrigerant R-12, which is different from the refrigerant R-22 usually used in domestic air conditioners. R-12 is suitable as the refrigerant for domestic refrigerators because it has a small compression ratio between a high pressure gas and a low pressure gas, and a longer life can be realized in refrigerators having such limited volume that they become popular for domestic use in the market. Using in domestic refrigerators a refrigerant which is different from the one of domestic air conditioners having the same cooling operational principle creates a problem wherein manufactures of domestic refrigerators and domestic air conditioners must have charging stands for different refrigerants, separately. The use of R-12 should be avoided in terms of a problem wherein decomposed R-12 decreases ozone outside the atmosphere, which is now topical throughout the world. In addition, there is also a problem wherein the provisions of the condenser 11 on the rear surface of the refrigerator and of the compressor 10 in the machine compartment 9 as shown in FIG. 19 make the inner volume of the refrigerator small.
Domestic refrigerators have a disadvantage in that most of them are placed in rooms such, as is kitchens as well known, and noise from the compressor gives discomfort to users.
Domestic refrigerators also have a disadvantage in that heat radiated from the condenser 11 increases the temperature in the room.
Recent domestic refrigerators are large-sized, and a variety of foods are housed in the refrigerators. It is said that food to be frozen had better be frozen as rapidly as possible in terms of freshness and good taste of the food as thawed for cooking. For that reason, domestic refrigerators are designed by the manufacturers to make the evaporation temperature in the evaporator 13 as low as possible. If the temperature of the evaporator 13 is lower (generally below -40.degree. C.), moisture in the air is condensed on the outer surface of the low pressure refrigerant pipe 94 (the tube exposed outside the refrigerators between the outlet of the evaporator 13 and the compressor 10) which is exposed in the machine compartment 9 in the rear portion of the refrigerators as shown in FIGS. 19 and 21. The condensed moisture creates frost-forming phenomenon. Because the conventional domestic refrigerators have a structure wherein the compressor 10 is housed in the machine compartment 9, it is difficult to arrange below the low pressure refrigerant pipe 94 and the compressor 10 a drain pan for reserving drainage which is produced by melting after the frost-forming phenomenon.
As a result, it is necessary with conventional refrigerators that the evaporation temperature in the evaporator 13 be above -40.degree. C. to avoid the frost-forming phenomenon even though the rapid freezing is desired.
It is an object of the present invention to dissolve such problems, and to provide an air conditioning system with a refrigerator integrated, wherein an air conditioning device and the refrigerator are operated by use of a common refrigerant, operating efficiency of the air conditioning device is improved, the compressor installed in the machine compartment of the refrigerator is replaced by an outdoor compressor of the air conditioning device, and the condenser normally provided on the rear surface of the refrigerator is replaced by a higher temperature of heat exchanger of the air conditioning device (it means the heat exchanger functions as a condenser i.e., an outdoor heat exchanger on cooling and an indoor heat exchanger on heating).